Cinematic portraits of potheads remain mired in a state of arrested development — from paranoid exploitation pics to joyfully lowbrow slacker comedies — waiting for a film like “Newlyweeds” to attempt a more mature mixture of marijuana and melodrama. Writer-director Shaka King’s alternately romantic, comedic and melancholy look at barely functioning dopeheads still has a ramshackle structure and its share of “Dude, can you believe how high we are?” silliness, but no one will confuse it for Cheech and Chong or Harold and Kumar.

For one thing, there’s a significant female presence, as King focuses on Nina (Trae Harris) and Lyle (Amari Cheatom), a young Brooklyn couple who hold down steady jobs during the day and never fail to smoke up at night. Lyle is a repo man for a sleazy rent-to-own company, while Nina is a beloved guide at the Brooklyn Children’s Museum. Distracted by a happy haze of ganja smoke, they never seem to notice their differing life goals: She dreams of traveling the world, he’s satisfied with the status quo. Although Lyle wants to make Nina happy, they both struggle with saving up money when there’s so much good hash waiting to be acquired and enjoyed.

For much of the film’s swift running time, “Newlyweeds” unspools with all the urgency and ambition usually associated with stoners. There’s not much plot, just a series of loosely connected happenings — Lyle and his co-worker Jackie (Tone Tank) repossess the wrong couch; Nina unwisely brings pot brownies to work; Lyle fantasizes he’s the star of a blaxploitation cop actioner dubbed “Tough Guys.”

King cites the low-key vibe of TV’s “Louie” as an inspiration, and auds will also be reminded of Spike Lee in the vivid snapshot of Brooklyn neighborhood life. Eventually Lyle spirals out of control (a descent brought on by the alcohol he usually avoids, rather than the weed he loves), and Nina decides she’s had enough. Lyle’s third-act revelation doesn’t dig any deeper than “you don’t know what you got ’til it’s gone,” but it’s a testament to King’s subtle scripting that you’re never quite sure how the relationship will ultimately shake out.

To the film’s credit, King neither demonizes nor glamorizes marijuana use. Still, it’s undeniable “Newlyweeds” suggests that both Lyle and Nina would be better off without a drug — any drug — to depend on.

Cheatom, a stage actor and Juilliard graduate briefly seen in the opening sequence of “Django Unchained,” manages the tricky task of making a forceful impression with a perpetually burnt-out character. He also creates a lovely, tender chemistry with Harris, a performance artist making a propitious screen debut. The small but sturdy ensemble also includes bit parts for character actors Isiah Whitlock Jr. and Hassan Johnson, both of “The Wire,” and Colman Domingo in an amusing turn as Nina’s Mongolian hash-hoarding colleague.